Figure 1.

LuxS biofilm defect is reversed by addition of DPD. (A) WT and LuxS biofilms were grown for 24 h or 72 h and stained with 0.2% CV, followed by measuring OD₅₇₀, N = 5. (B) Representative pictures of crystal violet stained C. difficile WT and luxS biofilms after 72 h. (C) Colony counts (vegetative cells) from biofilms (N = 7) after 24 h and 72 h. (D) The AI-2 precursor, DPD, was exogenously supplemented to LuxS at a concentration of 100 nM, followed by biofilm staining and quantitation with 0.2% CV after 72 h (N = 4). Error bars indicate SD, *p < 0.05, **p < 0.01, ***p < 0.001 as determined by Student’s t-test or by Mann-Whitney U test, ns- not significant.